There are multiple technical challenges present in current BMDS systems. These challenges include, but are not necessarily limited to, target discrimination, target-object mapping, and tracking accuracy.
Target discrimination, can be difficult in a complex threat environment using only the ground or surface-based sensor. Depending on the bandwidth of the surface-based sensor, it is highly likely that multiple objects will occupy the same range gate. In situations where multiple objects occupy the same range gate, they cannot be resolved in range. Further, the objects usually cannot be resolved in angle because of the distance to the target. The reliability of the target discrimination process could be improved when coupled with IR measurements from a seeker (or kill vehicle bus), but this introduces additional challenges and leads to the second technical challenge.
The second technical challenge is target-object mapping. Generation of the target-object map (“TOM”) is complicated because measurements reported by the surface-based sensor and a kill vehicle bus's onboard sensor may vary dramatically due to the difference in target signature in the different bands. Correlating measurements from IR and RF sensors is further complicated by the fact that the sensors are not co-located. In this case, a kill vehicle bus must correlate a 2-D IR representation of the threat complex with a 3-D RF representation from surface-based sensors. Given the extreme difference in aspects to the threat complex, this is very challenging.
The third technical challenge is tracking accuracy. The surface-based radar has limited angular accuracy due to the extreme range to the target. The limited angle resolution leads to range gates encompassing large volumes of space: nearby objects and high-density volume clutter are very likely to occupy the same range gate as the object of interest. Depending on the surrounding material in the threat complex, the target's signal-to-clutter ratio (“S/C”) can be degraded significantly, leading to a lower quality track. The situation can be improved marginally by integrating the kill vehicle bus's IR measurements; however, because the kill vehicle bus cannot produce its own range measurements, and because the sensors are not co-located, it can be difficult to measure the target's complete state. Adding to this problem, it is difficult to register the two sensors, that is, produce measurements in the same reference frame, because of the significant separation of the two sensors and the kill vehicle bus's extreme velocity.
Sensors of different phenomenologies may be utilized within a BMDS. Correlation of sensor observations remains a challenge. It remains desirable to provide technology for multiple phenomenologies to be present on interceptors of a BMDS adapted to prevent, minimize, reduce, or alleviate some of the sensor to sensor correlation challenges and enhance interceptor on-board tracking, discrimination, and target-object mapping capability.